I think the reason for the lid is to prevent the socket being stood on i.e. the plastic parts on the socket face might actually push out of place or crack if they had weight, from say a high heel, right in the centre of them. The NZ version, however, doesn't seem to have any plastic on the face at all.

Shutters have always been mandatory on those BS1363 sockets. So the lid's nothing to do with protecting kids from shoving something into them. They're as likely to do that with a wall socket as they are a floor socket.

As you can see all of the BS1363 sockets have a plastic part in the centre:

[Linked Image from knappelectrical.co.uk]
Even when fully metal clad

If there is a schuko or French version you'd have to have a lid or you'd fall in!

[Linked Image from swc.de]

I also suspect that the lid prevents it from gathering dust and generally looking ugly too.

[This message has been edited by djk (edited 07-08-2005).]